Fuel Cell is an Entity of Modern Grids

Development of information and communication technology helps real-time management and control of distributed energy resources (DERs) connected to the grid. At present, utilities are interested to modernize their power grid through the advancement of smart grid.

A smart grid is an electrical grid which extensively uses the digital communication to manage energy entities including DERs, electrical vehicles, and smart energy meters to minimize the mismatch between generation and load within the grid.

The development of the fuel cell began with a human effort towards space exploration. The electricity needs of all the commander vehicles in the Apollo project in the 60s’ and 70s’ were provided by fuel cells. The justification was simple and clear. The rocket motor in the vehicles took pure hydrogen and oxygen as fuel, which were the same chemicals necessary for the operation of the fuel cells on board. Moreover, the by-product water was used for drinking and humidifying the atmosphere of the space capsule [1]. Then, the technology found a completely different application, electric vehicle (EV). The amount of EVs connected to the smart grid is believed to be large in the near future as EVs are considered as a greener solution for the carbon emission issue. The recent research and developments on the fuel cell electric vehicle (FCEV) have attracted the vehicular industry. Fuel cells are devices that utilize the electrochemical process to convert chemical energy in a fuel to electrical energy. The produced electrical energy can be used to power electric vehicles, electronic devices, house and the excess energy can be delivered to the grid. Many different types of fuel cells can be constructed from different chemical reactions. In general, those fuel cells can be categorized according to the electrolyte used in the cell. However, for vehicular technology, the usual choice is polymer electrolyte membrane fuel cells (PEMFC). Apart from the emerging FCEV market, the biggest market for the PEM fuel cell is the application of back-up power supply for remotely located electronic outposts such as cell phone towers. Fuel cells also have an expanding presence in the indoor fork-lifter power pack application because of zero-emission characteristics. Conventional fuel such as natural gas can be converted to hydrogen with the necessary purity after reformation. This adds to the suitability of the technology in the diverse markets.

Another interesting application of the fuel cell is rural electrification.

A complete closed-loop pilot project based on fuel cell is built to electrify Stuart Island of Washington state. Solar panels are used to power an electrolyzer which makes hydrogen. Then, the hydrogen is used in fuel cells to produce dc current which is converted to ac current by an inverter to supply the loads [2].

The research and developments that take place at RTDS Technologies Inc. are always in line with advancements in the electrical industry. This time, we are proud to introduce the real-time simulation model of the PEMFC.

Operation of the Polymer Electrolyte Membrane Fuel Cell

The functional diagram of a polymer electrolyte membrane fuel cell (PEMFC) is shown in Figure 1. The anode and the cathode are separated by an electrolyte that is based on polymer electrolyte membrane.

Figure 1 – Functional diagram of fuel cell

At the anode, a hydrogen molecule will decompose into two hydrogen ions (H+) and two electrons (e–). Typically, a catalyst is used to boost the rate of reaction. Since the electrolyte behaves like a high resistance to the electrons and low resistance to the proton, the hydrogen ions will pass through the electrolyte while the electrons flow through the external load. At the Cathode, the oxygen ion (O2-) will combine with two hydrogen ion (H+) and form water (H2O) that will carry out the heat produced by the fuel cell reactions.

The RTDS Fuel Cell Model

The RTDS fuel cell model represents the PEM type fuel cell. In particular, this model attempts to depict the electrical aspect of a real fuel cell system known as ‘SR-12’ from a company named ‘Avista Labs’ (now ‘ReliON’). The fuel cell system is described further in [3, 4]. The draft icon of the model is shown in Figure 2. The model has two power system nodes namely Cathode and Anode. The model has three control inputs, which are the cell temperature (Tcell) in Celsius, the anode pressure (Pa) in atm, and cathode pressure (Pc) in atm. This model also requires the user to enter parameters such as charging capacitance per cell, cell area overall flow delay, rated voltage and current, and initial temperature and pressure values.

Figure 2 – Draft icon of the fuel cell model in RTDS

The PEMFC model enriches our latest release of RSCAD software that is available on our website www.rtds.com. More information of the above fuel cell model can be found in the help file associated with the model. Should you have any questions, please do not hesitate to contact us at support@rtds.com.

OUR COMPANY

Being the first of its kind, the RTDS® Simulator is the world’s benchmark for performing real time power system simulation. With satisfied customers in 42 countries across the globe and over 1400 units in operation, RTDS Technologies is the undisputed world leader in our craft. We introduced the world’s very first fully digital real time power system simulator in 1989.

RTDS Technologies continues to lead the way with our world-class, in-house research and development department. Our company is committed to innovation. We are continually developing our hardware, software, and support services in response to the needs of our customers.